<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>双双飞翼三栏布局</title>
    <style>
        body{
            padding-left: 200px;
            padding-right:300px;
        }
        .main{
            width:100%;
            height:500px;
            background-color: yellow;
            float:left;
        }
        .left{
            width:200px;
            height:500px;
            background-color: pink;
            float:left;
            margin-left:-100%;
            position: relative;
            left:-200px;
        }
        .right{
            width:300px;
            height:500px;
            background-color: blueviolet;
            float:right;
            margin-left:-300px;
            position: relative;
            right:-300px;
        }
    </style>
</head>
<body>
<div class="main">sdfjdshgjkdfbvjhbfgjdsbfgshdf</div>
<div class="left"></div>
<div class="right"></div>

</body>
</html>